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Biology subjects

Palumbo, E.

Publications and source records attributed to Palumbo, E..

9 recordsLinked to original sources

Shamonda virus EU1 in Northern Italy, August 2026.

Background Following the emergence of a novel Shamonda-like virus (SHAV) in Europe, suspected clinical cases in dairy cattle were reported in Northeastern Italy. Investigation was required in dairy cattle in Northeastern Italy. Methods Samples were collected from 28 farms displaying fever and reduced milk yield and were screened using molecular methods (PanSimbu real-time RT-PCR followed by Sanger sequencing and differential PCRs for SBV/BTV). Positive samples were subsequently confirmed by Sanger sequencing and selected samples underwent whole-genome sequencing using a metagenomic approach. Results Twenty-four among sera and blood samples from 12 farms tested positive for SHAV. WGS confirmed that Italian strains share maximum identity with the European SHAV-EU1 clade. Limitations This study concerns the results of clinical investigations on suspected cases in the two autonomous provinces of Trento and Bolzano. At present, it is not possible to infer on the circulation of the virus in other Italian provinces. Conclusions This study documents the first detection and genetic characterization of SHAV-EU1 in Italian cattle, indicating active circulation of this virus across Europe. Its identification in two north-eastern Italian provinces does not rule out wider, undetected circulation. In this regard, assessing its geographical extent requires careful evaluation, just as much remains to be discovered about its host range and the severity of symptoms.

microbiology↗

GENCODE: massively expanding the lncRNA catalog through capture long-read RNA sequencing

Accurate and complete gene annotations are indispensable for understanding how genome sequences encode biological functions. For more than twenty years, the GENCODE consortium has developed reference annotations for the human and mouse genomes, becoming a foundation for biomedical and genomics communities worldwide. Nevertheless, collections of important yet poorly-understood gene classes like long non-coding RNAs (lncRNAs) remain incomplete and scattered across multiple, uncoordinated catalogs. To address this, GENCODE has undertaken the most comprehensive lncRNA annotation effort to date. This is founded on the manually supervised computational annotation of full-length targeted long-read sequencing, on matched embryonic and adult tissues, of orthologous regions in human and mouse. Altogether 17,931 human genes (140,268 transcripts) and 22,784 mouse genes (136,169 transcripts) have been added to the GENCODE catalog representing a 2-fold and 6-fold growth in transcripts, respectively - the greatest increase in the number of annotated human genes since the sequencing of the human genome. Our targeted design assigned human-mouse orthologs at a rate beyond previous studies, tripling the number of human disease-associated lncRNAs that have mouse orthologs. Novel lncRNA genes consistently exhibit biological signals of functionality, and they greatly enhance the functional interpretability of the human genome. While poorly expressed in bulk RNA-Seq samples, many of them are highly expressed in specific cell populations, maybe even contributing to cell-type determination. The expanded GENCODE lncRNA annotations mark a critical step toward deciphering the human and mouse genomes.

genomics↗

The Drosophila cancer-germline, head-to-head gene pair TrxT and dhd is dispensable for normal brain development but plays a major role in l(3)malignant brain tumour growth.

Drosophila thioredoxins Deadhead (Dhd) and Thioredoxin-T (TrxT) are encoded by a head-to-head gene pair in the X chromosome. Akin to human cancer-germline (CG) genes, dhd and TrxT expression is normally sex and germline specific, but becomes upregulated in brain tumours of either sex caused by mutation in l(3)malignant brain tumour (l(3)mbt). Using CRISPR/Cas9-mediated knock-out alleles and RNA-seq, we show that while both TrxT and dhd are dispensable for normal brain development, each of them has a significant but partial effect on l(3)mbt brain tumour development as well as on tumour-linked transcriptomic signatures. Moreover, this effect is enhanced by the concomitant removal of both thioredoxins that strongly inhibits l(3)mbt larval brain tumour traits, reduces gene expression differences between tumour and wild-type tissue, and essentially erases all traces of gene expression differences between tumours from larvae of different sex. These results show that TrxT and dhd play a major synergistic role in the emergence of l(3)mbt tumour-linked transcriptomic signatures and tumour development, which is remarkable taking into account that these two genes are never expressed together under normal conditions. We have also found that TrxT is crucial but dhd has no effect on the growth of male-derived l(3)mbt allografts, hence suggesting that the initial stages of tumour development and sustained, long-term tumour growth may depend upon different molecular pathways. In humans, head-to-head inverted gene pairs are abundant among the CG genes that map to the X chromosome, some of which have been shown to work as a unit cancer. Our results identify the first instance of an X-linked, head-to-head CG gene pair in Drosophila and underpin the potential of such CG genes that are dispensable for normal development and homeostasis of somatic tissue, as targets to curtail malignant growth with minimal impact on overall health.

cancer biology↗

CapTrap-Seq: A platform-agnostic and quantitative approach for high-fidelity full-length RNA transcript sequencing

Long-read RNA sequencing is essential to produce accurate and exhaustive annotation of eukaryotic genomes. Despite advancements in throughput and accuracy, achieving reliable end-to-end identification of RNA transcripts remains a challenge for long-read sequencing methods. To address this limitation, we developed CapTrap-seq, a cDNA library preparation method, which combines the Cap-trapping strategy with oligo(dT) priming to detect 5capped, full-length transcripts, together with the data processing pipeline LyRic. We benchmarked CapTrap-seq and other popular RNA-seq library preparation protocols in a number of human tissues using both ONT and PacBio sequencing. To assess the accuracy of the transcript models produced, we introduced a capping strategy for synthetic RNA spike-in sequences that mimics the natural 5cap formation in RNA spike-in molecules. We found that the vast majority (up to 90%) of transcript models that LyRic derives from CapTrap-seq reads are full-length. This makes it possible to produce highly accurate annotations with minimal human intervention.

genomics↗

Brain transcriptomic profiling reveals common alterations across neurodegenerative and psychiatric disorders

Neurodegenerative and neuropsychiatric disorders (ND-NPs) are multifactorial, polygenic and complex behavioral phenotypes caused by brain abnormalities. Large-scale collaborative efforts have tried to identify the genetic architecture of these conditions. However, specific and shared underlying molecular pathobiology of brain illnesses is not clear. Here, we examine transcriptome-wide characterization of eight conditions, using a total of 2,633 post-mortem brain samples from patients with Alzheimers disease (AD), Parkinsons disease (PD), Progressive Supranuclear Palsy (PSP), Pathological Aging (PA), Autism Spectrum Disorder (ASD), Schizophrenia (Scz), Major Depressive Disorder (MDD), and Bipolar Disorder (BP)-in comparison with 2,078 brain samples from matched control subjects. Similar transcriptome alterations were observed between NDs and NPs with the top correlations obtained between Scz-BP, ASD-PD, AD-PD, and Scz-ASD. Region-specific comparisons also revealed shared transcriptome alterations in frontal and temporal lobes across NPs and NDs. Co-expression network analysis identified coordinated dysregulations of cell-type-specific modules across NDs and NPs. This study provides a transcriptomic framework to understand the molecular alterations of NPs and NDs through their shared- and specific gene expression in the brain.

neuroscience↗

Dynamics of gene expression and chromatin marking during cell state transition

We have monitored the transcriptomic and epigenomic status of cells at twelve time-points during the transdifferentiation of human pre-B cells into macrophages. Using this data, we have investigated some fundamental questions regarding the role of chromatin in gene expression. We have found that, over time, genes are characterized by a limited number of chromatin states (combinations of histone modifications), and that, consistently, chromatin changes over genes tend to occur in a coordinated manner. We have observed strong association between these changes and gene expression only at the time of initial gene activation. Activation is preceded by H3K4me1 and H3K4me2, and followed in a precise order by most other histone modifications. Further changes in gene expression, comparable or even stronger than those at initial activation, occur without associated changes in histone modifications. The data generated here constitutes, thus, a unique resource to investigate transcriptomic and epigenomic dynamics during a differentiation process.

genomics↗

bsAS, an antisense long non-coding RNA, controls cell fate through regulation of blistered/DSRF isoform expression

SummaryNatural Antisense Transcripts (NATs) are long non-coding RNAs (lncRNAs) that overlap coding genes in the opposite strand. NATs roles have been related to gene regulation through different mechanisms, including post-transcriptional RNA processing. With the aim to identify NATs with potential regulatory function during fly development, we generated RNA-Seq data in eye-antenna, leg, and wing at third instar larvae. Among the candidate NATs, we found bsAS, antisense to bs/DSRF, a gene involved in wing development and neural processes. Through the analysis of the RNA-Seq data, we found that these two different functions are carried out by the two different protein isoforms encoded in the bs gene. We also found that the usage of these isoforms is regulated by bsAS. This regulation is essential for the correct determination of cell fate during Drosophila development, as bsAS knockouts show highly aberrant phenotypes. bs regulation by bsAS is mediated by the specific physical interaction of the bsAS promoter with the promoters of bs, and it likely involves a mechanism, where expression of bsAS leads to the collision of RNA polymerases acting in opposite directions, preventing the elongation of the longer isoforms of bs, the ones carrying the neural related functions. Evolutionary analysis suggests that the bsAS NAT emerged simultaneously to the long-short isoform structure of bs, preceding the emergence of wings in insects, and maybe related to regulation of neural differentiation.

molecular biology↗

Comparative analysis of neutrophil and monocyte epigenomes

Neutrophils and monocytes provide a first line of defense against infections as part of the innate immune system. Here we report the integrated analysis of transcriptomic and epigenetic landscapes for circulating monocytes and neutrophils with the aim to enable downstream interpretation and functional validation of key regulatory elements in health and disease. We collected RNA-seq data, ChIP-seq of six histone modifications and of DNA methylation by bisulfite sequencing at base pair resolution from up to 6 individuals per cell type. Chromatin segmentation analyses suggested that monocytes have a higher number of cell-specific enhancer regions (4-fold) compared to neutrophils. This highly plastic epigenome is likely indicative of the greater differentiation potential of monocytes into macrophages, dendritic cells and osteoclasts. In contrast, most of the neutrophil-specific features tend to be characterized by repressed chromatin, reflective of their status as terminally differentiated cells. Enhancers were the regions where most of differences in DNA methylation between cells were observed, with monocyte-specific enhancers being generally hypomethylated. Monocytes show a substantially higher gene expression levels than neutrophils, in line with epigenomic analysis revealing that gene more active elements in monocytes. Our analyses suggest that the overexpression of c-Myc in monocytes and its binding to monocyte-specific enhancers could be an important contributor to these differences. Altogether, our study provides a comprehensive epigenetic chart of chromatin states in primary human neutrophils and monocytes, thus providing a valuable resource for studying the regulation of the human innate immune system.

genomics↗

LncATLAS database for subcellular localisation of long noncoding RNAs

BackgroundThe subcellular localisation of long noncoding RNAs (lncRNAs) holds valuable clues to their molecular function. However, measuring localisation of newly-discovered lncRNAs involves time-consuming and costly experimental methods.\n\nResultsWe have created \"LncATLAS\", a comprehensive resource of lncRNA localisation in human cells based on RNA-sequencing datasets. Altogether, 6768 GENCODE-annotated lncRNAs are represented across various compartments of 15 cell lines. We introduce \"Relative concentration index\" (RCI) as a useful measure of localisation derived from ensemble RNAseq measurements. LncATLAS is accessible through an intuitive and informative webserver, from which lncRNAs of interest are accessed using identifiers or names. Localisation is presented across cell types and organelles, and may be compared to the distribution of all other genes. Publication-quality figures and raw data tables are automatically generated with each query, and the entire dataset is also available to download.\n\nConclusionsLncATLAS makes lncRNA subcellular localisation data available to the widest possible number of researchers. It is available at lncATLAS.crg.eu.

bioinformatics↗